The Otherworlder, Exploring the Dungeon, Vol. 3 (Light Novel): Rhora the Deranged Volume 3

Though the loss of Arvin and Zenobia still weighs heavy on their hearts, Souya and his remaining party members steel themselves to take on the dungeon once again. This time, they're up against their greatest trial yet: The Deranged Stratum, a perilous section of the labyrinth where a malevolent being has been abducting countless victims. And it looks like Lana is its next target...